BOSTON — There’s no way the Bruins will beat Montreal in their Eastern Conference quarterfinal series that starts tonight at TD Garden if they’re going to be a one-line or even two-line team.

That doesn’t mean the Bruins need four lines of scoring, they just need to have a quartet of trios going all out every shift. And if they’re working hard, offensive contributions might come.

The “third line” of Chris Kelly, Rich Peverley and Michael Ryder is definitely in a produce-to-play predicament. If that trio doesn’t play at its speedy, aggressive best, one could foresee head coach Claude Julien leaning on his energy line of Daniel Paille, Gregory Campbell and Shawn Thornton — three players that combined for an impressive 29 goals in the regular season — in more crucial situations.

For what it’s worth, considering the Bruins more or less played to just not get hurt over the final week to 10 days of the regular season, Kelly, Peverely and Ryder showed some flashes that they’re ready to bust out offensively during that stretch. Kelly scored his only two Bruins goals, including a tip-in in the closing seconds of the regular season at New Jersey, over the final four contests. Ryder clinched a win with a penalty-shot goal. And Peverley potted a goal in each of the last two games.

“I think obviously we’re getting more comfortable with one another,” said Kelly this morning after he took part in an optional morning skate. “And I think we’re just going out there and playing and having fun. Obviously it’s been nice to contribute a little bit offensively lately. But I think in the past we’d been playing well at both ends.”

For his career, Kelly has produced 13 points (four goals) in 36 NHL playoff games. In Ottawa’s run to the Stanley Cup Final is 2007, he put up 3-4-7 totals in 20 games.

“When team has success, I think individuals have success. That’s always been, I think, a good philosophy to look at,” said Kelly when asked to assess his past postseason performances.

While Peverely only has six games of playoff experience (he registered two assists) in his past, Ryder has been a playoff beast dating back to his days of junior hockey with Hull of the QMJHL. Keeping focused on just the NHL, Ryder has produced 18 points in 24 Bruins playoff games. There has to be a reason that even after lackluster regular-season performances like his 2009-10 season, Ryder tends to come through when the stakes are raised.

“Maybe pucks are going in for me. Maybe it’s just bearing down a little more, and knowing that in the playoffs any little momentum swing or goal here or there could change a series,” said Ryder about his prolific postseason play. “And I think that’s the big thing about it, that’s what’s the most fun. In a series, you never give up and everybody starts off with a clean slate.”

In the case of the Bruins’ third line, those three players would probably rather there be a little left on the slate as the playoffs start because before their strong finish there wasn’t much on that slate at all. The tag of third line or fourth line is very interchangeable. If Kelly, Peverley and Ryder don’t play their best, they could find that out.

I’m happy if this line simply keeps the puck out of their own end, and refrains from committing penalties. Anything they score is gravy… just don’t want them to be a liability. That’s the one plus of Kelly – he’s reliable positionally, and he battles a bit. Plus this line is a good option for important faceoffs.

But – I’ll really be looking to PC to revamp the make up of this line for next year.

Combine Ryder’s playoff history with the fact he’ll be a UFA and I expect to see some urgency from him. I’ve been saying for a while now that our third line will often determine our fate as we march through the playoffs.